Предмет: Математика, автор: bananalive1516

Стрекоза делает 1600 взмахов крыльями в секкнду.Сколько взмахов крыльями она сделает за минуту

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Автор ответа: tatsach

2

=1600*60=96000
..............................

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Computers have been used since the 1950s for the storage and processing of data. An important point to note is that the main memory of a computer provides only temporary storage; any data stored in main memory is lost when the power is turned off. For the permanent storageof data, one must turn to auxiliary storage, primarily magnetic and optical media such as tapes, disks, and CDs. Data is stored on such media but must be read into main memory for processing.

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When so-called direct-access storage devices (DASD), primarily magnetic disks) were developed, it became possible to access a random data block on the disk. (A data block is the unit of transfer between main memory and auxiliary storage and usually consists of several records.) Files can then be indexed so that an arbitrary record can be located and fetched (loaded into the main memory).

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9. What does an index of a file consist of?

10. How are indexes navigated?

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